Can Your Dock Fenders Withstand the Impact of Large Vessels? — The Complete Answer from Wuxi ChuncoTech Rubber's SA-Type Rubber Fenders

In our previous article, "Why Do Rubber Fenders Fail at the Welds? How to Choose Blow-Molded Fenders That Last," we explored the causes of weld failure and how to select durable blow-molded fenders. Today, we turn our attention from welding processes to another core fender product widely used in large terminals, liquefied natural gas (LNG) receiving terminals, container terminals, and bulk cargo ports — SA-type rubber fenders (Super Arch Fenders) . If you manage a large port, you've likely asked yourself: Why do some fenders develop cracks after just a few berthings? Why are reaction force calculations always off? Why do fenders need replacement within five years of installation? The answers often lie in the fender's design philosophy, material formulation, and manufacturing processes.

I. Is Your Port Suffering from "Invisible" Impact Risks?

Port operations managers and engineers frequently face these challenges:

• Vessel tonnage keeps increasing — existing fender systems have insufficient energy absorption capacity, making every berthing a nerve-wracking event.

• Longitudinal cracks appear on fender surfaces — the fender hasn't completely failed yet, but no one knows if the next berthing will be the one that causes disaster.

• Inaccurate reaction force calculations — leading to dock structures that are either over-designed (wasting investment) or under-designed (creating safety hazards).

• Difficult fender replacement — large fenders can weigh several tons each, requiring heavy lifting equipment and high construction costs.

• High-tidal-range ports — the same fender system must accommodate both light and fully loaded vessels at different berthing heights.

These problems directly impact operational safety, berthing efficiency, and maintenance costs. The SA-type rubber fender — full name Super Arch Fender— is precisely designed to solve these challenges for large terminal applications.

At Wuxi ChuncoTech Rubber , we believe: The fender system for large terminals should never become the "weak link" of the entire berth. Our SA-type fenders deliver high energy absorption, low reaction force, and long service life through scientific arch geometry, optimized rubber formulations, and rigorous manufacturing processes.

II. What Exactly Is an SA-Type Rubber Fender? And Why Is It Called "Super Arch"?

The SA-type rubber fender (Super Arch Fender) is an upgraded version of the Arch Fender. Its name comes from the distinctive arch-shaped cross-section — a structural geometry similar to bridge arches. This design perfectly combines rubber elasticity with the mechanical advantages of an arch:

• High energy absorption: When compressed, the arch structure undergoes bending deformation, stretching and compressing rubber molecular chains to convert vessel kinetic energy into heat. Compared to traditional D-type or V-type fenders, the SA-type achieves 30-50% higher energy absorption efficiency per unit weight.

• Low reaction force: For the same amount of energy absorbed, SA-type fenders generate lower reaction forces on the dock structure. This means docks can be designed more economically, or existing docks can accommodate larger vessels without structural modifications.

• Stable force-deflection curve: The compression force of SA-type fenders rises smoothly with compression — no "sudden jumps" or "plateaus" — allowing dock design engineers to accurately calculate berthing energy.

• High compression capacity: SA-type fenders are designed for compression up to 50-57.5% (depending on model), providing ample safety margin under extreme berthing conditions.

Our SA-type fenders are manufactured from high-strength natural rubber (NR) . We also offer ultra-low temperature formulations (-50°C) , ozone-resistant EPDM formulations, and flame-retardant formulations upon request.

III. Where Do SA-Type Fenders Perform Best? Core Applications

SA-type rubber fenders are the "workhorses" for large terminals, suitable for the following scenarios:

1. Large Container Terminals

Container ships are characterized by large tonnage (exceeding 240,000 deadweight tons), high freeboard, and precise but extremely high-energy berthing speeds. The high energy absorption capacity of SA-type fenders allows them to absorb the berthing energy of large container ships within limited space while protecting both dock structures and vessels.

2. Liquefied Natural Gas (LNG) Receiving Terminals

LNG vessels have extremely high requirements for berthing smoothness — any severe impact can create safety hazards. The low reaction force characteristicsand smooth force-deflection curve of SA-type fenders provide a "soft landing" berthing experience, minimizing impacts on LNG cargo tanks and loading arms.

3. Bulk Cargo Terminals (Iron Ore, Coal, Grain)

Bulk carriers berth frequently, have large tonnage, and come in diverse vessel types. The durability and fatigue resistance of SA-type fenders withstand multiple daily berthing impacts, while their wide compression rangeaccommodates vessels with different draft depths.

4. Cruise Terminals

Cruise passengers have extremely high expectations for comfort. SA-type fenders minimize berthing impacts and vibrations to the greatest extent, making passengers almost unaware of the vessel contacting the dock.

5. High-Tidal-Range Ports (Following Our Previous Discussion)

As discussed in our previous article on high-tidal-range ports, SA-type fenders can be installed vertically or in multi-tier arrangements to accommodate tidal variations of several meters. Their uniform compression characteristics ensure consistent protection performance at any tide level.

IV. Real Test Data: How Powerful Are SA-Type Fenders?

We conducted comprehensive testing of Wuxi ChuncoTech Rubber 's SA-type fenders in accordance with PIANC (Permanent International Association of Navigation Congresses) and ISO 17357 standards:

Energy absorption and reaction force (using SA400 model as example, length 3000mm) :

At 25% compression: Reaction force of 250-300 kN/m , energy absorption of 35-45 kN·m/m .

At 37.5% compression: Reaction force of 400-480 kN/m , energy absorption of 70-85 kN·m/m .

At 50% compression: Reaction force of 600-700 kN/m , energy absorption of 130-160 kN·m/m .

At 57.5% compression (maximum) : Reaction force of 750-850 kN/m , energy absorption of 180-210 kN·m/m .

Note: Specific values vary depending on rubber hardness and formulation.

Compression set test (70°C, 22 hours) : Our SA-type fenders achieve a compression set of less than 5% — meaning even after long-term compression, they return to their original shape when released.

Aging resistance test (70°C, 168 hours hot air aging) : Tensile strength retention exceeds 90% , elongation retention exceeds 85% .

Ultimate compression test: SA-type fenders can be compressed to 70% without failure — a safety margin far exceeding the industry requirement of 20% .

Data source: Joint test report from Wuxi ChuncoTech Rubber internal laboratory and third-party testing institute

V. Real Customer Story: How SA-Type Fenders Solved an LNG Terminal's Berthing Problems

Background: A coastal LNG receiving terminal with an annual receiving capacity of 3 million tons. The existing fender system used outdated non-standard fenders with several problems: (1) excessively high reaction forces pushing dock structural stress close to design limits; (2) insufficient energy absorption capacity, leaving inadequate safety margins for large LNG vessel berthings; (3) surface cracks already appearing on existing fenders, indicating end of service life.

Solution: The engineering team at Wuxi ChuncoTech Rubber conducted on-site surveys and berthing energy calculations, recommending SA400 rubber fenders (length 3500mm, 12 units total) to replace the existing fenders. We also provided complete installation drawings, bolt torque specifications, and maintenance guidelines.

Results: After replacement, berthing impacts from LNG vessels were noticeably reduced. Dock structural stresses decreased by 25% , and safety margins were significantly increased. After two years of operation, the fenders showed no surface cracks, no deformation, and stable performance. The terminal's engineer reported: "Since switching to SA-type fenders, berthing has been much more reassuring. Before, we used to stare at the stress monitors every time a large vessel berthed. Now, we don't need to at all."

VI. Your Port Deserves a Better Fender System

Is your port facing fender upgrade pressure due to increasing vessel sizes? Are you searching for a reliable fender with high energy absorption and low reaction force? Is your maintenance team tired of frequently replacing fenders?

It's time to choose a truly professional fender for your port. Wuxi ChuncoTech Rubber 's SA-type rubber fenders — with scientific arch design, 50%+ large compression capacity, and smooth force-deflection curves — provide 20+ years of reliable protection for your port.

Take action now:

1. Visit our website https://www.chuncotechrubber.com to download our "SA-Type Rubber Fender Product Selection Guide and Performance Data Sheet."

2. Contact our marine fender engineering team — provide your port parameters, vessel types, and berthing energy requirements. We will deliver free fender selection recommendations within 48 hours.

3. Request free samples or detailed test reports — see the superior performance of SA-type fenders for yourself.

Wuxi ChuncoTech Rubber — Protecting every safe berthing with professional fender technology.